Fluid pressure brake



Jan. V25, 1938. E. R. FITCH ET AL 2,106,480

FLU ID PRESSURE BRAKE Filed Oct. 23, 1936 Z-SheetS-Sheei l 7 Aux/P55 23r -Fig 64 3/ 70 656572 670C? 6/60 ATTORNEY Jan' 25 1938- E, R. FITCH ETAx. 2,106,480

FLUID PRESSURE BRAKE l Filed 0G12. 23, 1956 2 Sheets-Sheet 2 62 Fig 5.if 4g Ja J/ 6? y! 6% ELLE FTPCH BQLEN TMCCLUHE 4.a /02 /03 246 ATTORNEY Patented Jan. 25, 1938 s'rrss Are'r FLUID PRESSURE BRAKE ApplicationOctober 23, 1936, Serial No. 107,212

21 Claims.

This invention relates to uid pressure brake equipment which is adaptedto be changed over or conditioned to meet the braking requirements ofeach of a plurality of classes of railway train service, such forinstance, as passenger, express and freight train service, and relatesmore particularly to that type of equipment disclosed in the pendingapplications of Clyde C. Farmer and Ellis E. Hewitt, Serial No. 743,546,filed September 11, 1934, and Serial No. 94,372, filed August 5, 1936.

To meet the braking requirements of the several classes of railway trainservice above mentioned, this type of fluid pressure brake equipment isadapted to be changed over or conditioned for different classes ofrailway train service by means of either a manually operativechange-over valve device such as is shown in the above mentioned Farmerand Hewitt application, Serial No. 743,546 or by means of anautomatically operative changeover valve device of the type shown in theabove mentioned Farmer and Hewitt application, Serial No. 94,372, filedAugust 5, 1936. Other automatically'operative change-over valve devicessuch as shown in a pending application of Clyde C. Farmer and Ellis E.Hewitt, Serial No. 747,734, filed October 10, 1934 and in the patent ofClyde C. Farmer, No. 2,035,056 may be employed.

In each of the aforementioned classes of train service, to insure theprompt movement of the triple valve parts to service position and topropogate such movement throughout the length of the train, theequipment disclosed in the above mentioned pending application, SerialNo. 743,546 is provided with means for effecting local quick servicereductions in brake pipe pressure. The quick service venting meansemployedin the equipment is adapted to function in each class of trainservice to effect an initial quick service reduction in brake pipepressure upon movement of the auX- iliary valve of the triple valvedevice relative to the main valve when the brake pipe pressure isreduced to initiate an application of the brakes. Following this quickservice reduction in brake pipe pressure the movable parts of the triplevalve device will move to brake application position in which a furtherquick service venting of fluid under pressure from this brake pipeoccurs.

In passenger train service, in'order to provide the desired flexibilityand smoothness of control of trains it is essential that the fluidpressure brake equipment on the cars of the train be capable ofoperation to effect a graduated release of the brakes. In express andfreight train operation the graduated release feature prohibitivelyslows up the release of the train brakes. Furthermore, cars having thegraduated release feature cannot be operated in the middle or rearportion of either express or freight trains without undesirable releasegraduations occurring when a direct release of the brakes is desired.From this it will be apparent that a fluid pressure brake equipment tobe suitable for use in passenger, ex-A press and freight train serviceshould be capable of being conditioned or changed-over to provide thegraduated release features for passenger train service and should alsobe capable of being conditioned or changed-over to annui or eliminatethe graduated release features for express and freight train service.

In the aforementioned pending applicationy of Clyde C. Farmer and EllisE. Hewitt, Serial No. 743,546, van equipment is shown and describedwhich embodies the quick service, graduated release and change-overfeatures above referred to. Although not shown, the equipment disclosedin the aforementioned pending application of Clyde C. Farmer and EllisE. Hewitt, Serial No. 94,372, is intended to embody the quick servicefeatures above referred to.

To graduate the release of the brakes on a train, the brake pipepressure is restored in steps or increments by moving the engineersbrake valve device back and forth between either release or runningposition and lap position. It is well known that when the brake valvedevice is moved to release or running position to initiate a release ofthe brakes, the brake pipe and associated parts of the equipment on thecars at the head end of the train will be charged to a higher pressurethan on the cars at the rear end of the train, and that when the brakevalve device is moved from either of these positions to the lapposition, in which the supply of fluid under pressure to the brake pipeis cut off, there will be a continued flow of fluid from the front endof the train toward the rear of the train, in other words, the brakepipe pressure on the front end of the train tends to equalize toward therear end of the train. This of course causes a reduction in brake pipepressure on the cars at the front end of the train which, with referenceto the type of equipment shown in the aforementioned applications SerialNo. 743,- 546 and Serial No. 94,372, may in some instances be greatenough to cause the triple valve piston and thereby the associatedauxiliary slide valve to move to initial quick service position eventhough such movement is resisted by the stabilizing mechanism which isshown in application Serial No. 743,546 and which may be embodied in thetriple valve device.

The principal object of the present invention is to provide a uidpressure brake equipment of the above mentioned type with meansoperative when the equipment is conditioned for passenger train servicefor closing the initial quick service venting communication uponeffecting an application of the brakes and for maintaining thiscommunication closed until such time as the brake cylinder pressure isreduced to a low degree, say for instance to around ve pounds, so as toprevent the local quick service venting of fluid from the brake pipewhen, in graduating the release of the brakes, the movable parts of thetriple valve device unintentionally assume their initial quick serviceventing position.

Other objects and advantages will apear in the following more detaileddescription of the invention.

In the accompanying drawings, Fig. l is a diagrammatic view of a fluidpressure brake equipment embodying the invention; Fig. 2 is an enlargeddiagrammatic sectional view of a portion of the equipment, thechange-over valve mechanism being shown in position for conditioning theequipment for passenger train service; Fig. 3 is a fragmentary sectionalview showing the change-over valve mechanism in position forconditioning the equipment for express train service; Fig. 4 is afragmentary sectional view showing a portion of the change-over valvemechanism in the position it assumes to condition the equipment forfreight train service; and Fig. 5 is a fragmentary detail sectional viewtaken on the line 5-5 of Fig. 2.

As shown in the drawings the equipment may comprise a brake pipe I, asignal pipe 2, a brake controlling valve device 3, a change-over valvemechanism 4, a brake cylinder control valve mechanism 5, a relay valvedevice 6, an auxiliary reservoir 7, an emergency reservoir 8, a volumereservoir 9, a supply reservoir I0, a take-up cylinder device and abrake cylinder I2.

The several parts of the equipment which have just been enumerated maybe substantially the same in construction and operation as thecorresponding parts of the equipment disclosed in the aforementionedpending application Serial No. 94,372, with but one exception, namely,the brake cylinder control mechanism 4 which embodies the additionalfeature of controlling the initial quick service communication leadingfrom the brake pipe to the usual quick service chamber and atmosphere,so that when the equipment is conditioned for passenger train servicethere will be no local quick service venting of fluid from the brakepipe when, in eiecting a graduated release of the brakes, the movableparts of the brake controlling valve device accidentally move to initialquick service position, all of which Will hereinafter more fully appear.

As shown the brake controlling valve device may comprise a pipe bracketI3 to one side of which is clamped the casing of a triple valve deviceI4 and to the opposite side of which is clamped the casing of anemergency valve device I5.

The casing of the triple valve device has formed therein a pistonchamber I5 containing a piston |`I having a stem I8 adapted to operate amain slide valve I9 and an auxiliary slide valve 2l) contained in avalve chamber 2| which is connected to the auxiliary reservoir 'Ithrough a passage 22 and a passage and pipe 23.

The piston stem, at a point located a short distance inwardly from therear end, is provided with a shoulder 24 which is adapted to engage arear end surface 25 of the main slide valve I9.

The rear end portion of the piston stem I8 is provided with a bore 26which is closed at one end by a plug 21 having screw-threaded connectionwith the stem, said plug being provided with a central bore 28. Belowthe lower surface of the major portion of the piston stem, the other endof the bore 26 is open. The inner end wall of the bore 26 forms a stopshoulder adapted to be engaged by a plunger 29 which is in slidableengagement with the piston stem within the bore 26. The plunger isprovided with a stem 30 which is slidably guided by the plug 2'1 withinthe bore 28. Interposed between and engaging one side of the plunger 29and plug 2l is a spring 3| which acts to normally maintain the plungerin engagement with the end wall of the bore 28. In this position, theface of the plunger will be closer to the rear surface 25 of the mainslide valve I9 than will be the outer face of the shoulder 24 of thepiston stem, so that in eiecting an application of the brakes, theplunger will engage the main slide valve and yieldably resist movementof the piston and auxiliary slide valve relative to the main slide valvebefore the shoulder 24 of the stem engages the main slide valve. Thepurpose of this is to stabilize the action of the equalizing valveparts, as will hereinafter more fully appear.

The construction of the emergency valve device I5 may be identical with-that of the emergency valve device shown and described in theaforementioned pending application of Clyde C. Farmer and Ellis E.Hewitt, Serial No. 743,546 and may have substantially the same operatingcharacteristics. In view of this, the details of construction and theoperating characteristics of the equipment which correspond with thoseof the equipment disclosed in said applications have, for the most part,been omitted from the present application so as to simplify the showingand the description of the invention.

As shown, the casing of the emergency valve device has formed therein apiston chamber 32 containing a piston 33 having a stem 34 adapted tooperate a main slide valve 35 and an auxiliary slide valve 36 containedin a chamber 3l which is connected by way of a passage 38 to a quickaction chamber 39 which is formed in the pipe bracket I3.

'Ihe rear end portion of the emergency piston stem 34 carries amechanism which is quite similar in construction to the stabilizingmechanism carried by the rear end portion of the triple valve pistonstem I8, and comprises a plunger 40 which is subject to the pressure ofa spring 4| interposed between and engaging the plunger and a plug 42having screw-threaded connection with the piston stem 34. 'Ihis plungeris movable a limited distance relative to the stem 34 and is slidablyguided within a bore 43 provided in the stem, and has a stern 44 whichis slidable within a bore 45 provided in the plug 42. This mechanism isadapted to cooperate with the main slide valve 35 to stabilize themovement of the emergency valve parts in effecting applications of thebrakes and is also adapted to cooperate with the main slide valve toassist lin shifting the emergency piston 33 and auxil- The brake pipe Iis in communication with both the equalizing piston chamber I6 and theemergency piston chamber 32 by way of a branch pipe and passage 46 and apassage 41.

The change-over valve mechanism 4 is identical in most respects with thecorresponding device of the aforementioned Farmer and Hewittapplication, Serial No. 94,372 and comprises a casing 48, which, in thepresent embodiment; of the invention, is secured to the casing of thetriple Valve device and comprises a change-over valve device and achange-over control valve device for controlling the operation of thechangeover valve device.

The change-over control valve device just referred to comprises spacedmovable abutments which, in the present embodiment of the invention, arein the form of flexible diaphragms 49 and 58, the diaphragm 49 having agreater face area than the diaphragm 59. At the outer or face side ofthe diaphragm 49 there is a chamber 5| which is constantly incommunication, through a passage and pipe 52, with the signal pipe 2.Leading from the passage 52 to the face of a slide valve seat 53 of thecasing 48 is a branch passage 54. At the outer or face side of thediaphragm 50 there is a chamber 55 which is connected to a passage 56leading to the face of the slide valve seat 53.

Between the diaphragme 49 and 50 there is a chamber 51 which is inconstant communication with the atmosphere by way of passage 58.Contained in this chamber 51 is a longitudinally movable stem 59 -whichis operatively engaged at one end by the diaphragm 49 and which isadapted to operate a slide valve 60 also contained in the chamber andslidably engaging the slide valve seat 53, said slide valve beingmaintained in close engagement with the seat by means of a springweighted rockable strut 6| which is interposed between the casing andthe back of the slide valve.

There is also contained in the chamber 51 a mechanism which, as willhereinafter more fully appear, is subject to the action of the diaphragm49 to control the operation of the stem 59 and consequently the slidevalve 69, said mechanism comprising a combined spring seat and stopmember 62 which is preferably arranged in longitudinal alignment withthe ste-m 59 and which, at its left hand end, is in operative engagementwith the diaphragm 58, said member being movable in the direction of itslengthand having a guide collar 63 which is slidably guided in a bushing64 secured to the casing.. This member 62 also has a stem 65 on whichthere is slidably mounted a movable stop 66 which is adapted to beengaged by an annular spring seat 61 interposed between the stop 86 andstem 59 and slidably guided by the casing.

Interposed between and operatively engaging the guide collar 63 and themovable stop 66 is a. coil spring 68, and interposed between andoperatively engaging the spring 91 and a spring seat 69 contained in thechamber 51 and abutting the inner end of the bushing 54 is a coil spring1i! which surrounds the spring 88. Movement of the spring seat 31 towardthe right by the action of the spring 10 is adapted to be limited by anannular stop shoulder 'il which may be integral with the casing andwhich extends into the path of travel of the spring seat. Movement ofthe stop 66 toward the right by the action of the spring 68 is limitedby means of an annular collar or snap ring 12 which is secured to thestem 65.

The change-over valve device comprises spaced pistons 13, 14, which arerigidly connected together by means of a piston stem 15 which is adaptedto shift a slide valve 16 to one or another of two change-over orconditioning positions, said Valve being contained in a chamber 11located between the pistons and constantly connected to the emergencyreservoir 8 throughv a passage 1.8 and a passage and pipe 19. This valvechamber is constantly connected to a control passage 88 leading to theface of the slide valve seat 53 of the change-over control valve device.

At the face side of the piston 13 there is a chamber 8i which isconnected toa control passage 82 leading to the control slide valveseat53, and at the face side of the piston 14 there is a chamber 83 which isconnected to a control pas- V= sage 84 leading to said slide valve seat53.

Contained in a chamber 85 of the casing of the change-over valvemechanism 4 is a brake.

cylinder build-up control valve 86 which is adapted to be operated by aiiexible diaphragm 81.

At the right hand or face side of the diaphragm there is a chamber 88which is connected to a passage 89 leading to the face of the controlslide valve seat 53. The valve 86 is adapted to seat on an annular seatrib 98 formed on the casing and when so seated, the portion of the faceof the valve which is within the seat rib is connected through a passage9| to a pas.- sage 92 leading to the seat of the change-over slide valveandto the brake cylinder control valve mechanism 5 as will hereinaftermore fully appear. The portion of the face of the valve which is on theoutside of the valve is connected through a restricted passage 93 to apassage 94 leading to a pipe 95 which is connected through a pasbrakecylinder 2 and the release of fluid underl pressure from the brakecylinder and is further for the purpose of controlling the charging ofthe supply reservoir with iiuid under pressure from the brake pipe. Thisrelay Valve device may be identical with the corresponding device fullyshown and described in the aforementioned pending application, SerialNo. '143,546 and in view of this a detailed description here of thedevice is deemed unnecessary. s l The brake cylinder control valvemechanism is provided for the purpose of cutting the relay Valve device5 into action when the pressure-of fluid in the take-'up brake cylinderhas been increased a predetermined amount as will hereinafter more fullyappear, and may comprise a control valve device and a pilot valvedevice.

The control valve device may comprise a piston 99 which is contained ina chamber |88 and which is subject to the pressure of a coil spring |0|contained in this chamber. The piston 99 is provided with a stem4 |92which is adapted` to operate a slide valve |93 contained in a chamber|84 which is connected through a passage |95 to the auxiliary reservoirpassage 23.

The pilot valve device of the brake cylinder control valve mechanism 5may comprise a piston |93 which is contained in a chamber |01 connectedto a passage |88 leading to the atmosphere, This piston |96 is subjectto the pressure sage 96 to the piston chamber 91 on the face 1410.

a chamber H2, which chamber, with the slide valve III in its normalrelease position, as shown `in Fig. 2, is connected to the take-upcylinder II through a passage and pipe H3. Mounted on the back of thepiston |06 is a gasket H4 which is adapted to seat on an annular seatrib H5. The slide valve I|| is at all times urged into close contactwith its seat by means of a spring Weighted rockable strut H6 which isinterposed between the valve and casing.

Mounted in the casing of the brake cylinder control valve mechanism 5 isa combined maintaining and release control Valve device I IlI which isprovided for the purpose of maintaining takeup cylinder pressureagainstrleakage when an application of the brakes is effected and ofcontrolling the release of iiuid under pressure from the take-upcylinder in releasing the brakes. This valve device may comprise aflexible diaphragm H8 having at one side a chamber H9 open through apassage |28 to the atmosphere and containing a spring i2! which isinterposed between and operatively engages the casing and one side ofthe diaphragm. At the opposite side of the diaphragm there is a chamber|22 which contains a valve |23 adapted to engage an annular seat rib |24formed on the casing. Normally the valve is held seated by the spring I2acting through the medium of the diaphragm, against the opposingpressure of a coil spring |25 of lesser value contained in the chamber|22. With the valve seated, the inner seated area of the valve isconnected through a passage |26 to passage H3 and the outer seated areais connected through a passage |21 to a passage |28 which leads from abrake control passage |29 to the seat for the slide valve |03 of thebrake cylinder control valve mechanism 5.

Associated with the emergency valve device and mounted in the casingthereof is a relay piston chamber pressure build-up control valve orinshot valve device |39 which is operative in eiecting an emergencyapplication of the brakes, only when the equipment is changed over orconditioned for freight train service, to eiect the operation of therelay valve device l to provide an initial inshot of fluid to the brakecylinder until a predetermined brake cylinder pressure (about liteenpounds) is developed and to then restrict the rate of flow of fluid tothe brake cylinder I2, in other words, the device |33 functions to pilotthe action of the relay valve device in eiecting an emergencyapplication of the brakes until such time as a timing valve |3| Which iscontrolled through the medium of a flexible diaphragm |32 operates toprovide a iinal inshot of fluid to effect the operation of the relayvalve device to provide a nal inshot of fluid to the brake cylinder.

This valve device |39 is similar in construction to the correspondingvalve mechanism fully described in the aforementioned pendingapplication, Serial No. 743,546, and briefly described, may comprise avalve |33 which is contained in a chamber |34 connected to the passage|29; there being a restriction |33 interposed in the passage at a pointadjacent the chamber |34. The device also comprises a valve piston |36having a stem |37 through the medium of which the operation of the valve|33 is controlled. Normally the valve piston I 36 is maintained insealing engagement with the casing by the action of a coil spring |38contained in a piston chamber |39 Which is connected through a passage|49 and a small volume reservoir I4| to a passage |42 leading to theseat of the emergency main slide valve 35, and when in this position thestem |3'iv maintains the valve |33 unseated against the action of aspring |43 tending to seat the valve.

With the valve |33 unseated, the valve chamber |34 is open to the volumereservoir 9 by way of a passage |44, a chamber |65, a passage |46 and apassage and pipe |47. The valve chamber |34 is also connected to thechamber |45 by Way of a restricted passage |48. The passage |46 isconnected through a choke |49 to the passage 94, so that the chamber |34is in communication with the piston chamber 91 of the relay valve device6.

The chamber |43 of the valve device |30 is also connected through arestricted passage |59 to a Valve chamber l5! at one side of theiiexible diaphragm |32 and containing the valve |3I. At the other sideof the diaphragm there is a chamber |52 which is connected in the usualmanner through a passage |53 to the emergency slide valve chamber 31.The inner seated area of the valve i3! is exposed to a chamber |54 whichis connected through a passage |55 to the valve chamber |34.

Associated with the valve device |30 is a safety valve device |56 whichmay be of the same construction as usually employed in universal valvedevices and is for the purpose of venting uid under pressure from thevolume reservoir 9 and relay piston chamber 91 to thereby limit thebrake cylinder pressure when the equipment is conditioned for passengertrain service and an overreduction in brake pipe pressure is eifected inmaking a service application of the brakes, the flow of uid to thesafety valve device being by Way of chamber |39 and a passage |52'leading from the chamber. This safety valve device is set to vent uidfrom said reservoir and piston chamber When the pressure therein hasbeen increased to around sixty-three pounds. By thus limiting thepressure in the reservoir chamber, the relay valve device 3 willfunction to correspondingly limit the brake cylinder pressure. It willhere be understood that the safety valve device only functions to limitthe degree of fluid pressure build up in the volume reservoir 9 andrelay piston chamber 9'! in effecting a service application of thebrakes with the equipment conditioned for passenger train service and isrendered inoperative by the emergency valve when an emergencyapplication of the brakes is initiated.

The take-up cylinder device II is associated with the brake cylinder I2and may be of substantially the same construction and for the samepurpose as the corresponding device disclosed in a patent to Clyde C.Farmer, No. 2,004,654, issued June l1, 1935. This device, as Willhereinafter more fully appear, is adapted to operate to take up slack inthe brake rigging.

and to move the usual brake shoes into light engagement Withvthe carwheels before the brake cylinder I2 is caused to operate to applybraking force to the brake rigging.

The equipment also comprises a quick serviceevice duction in brake pipepressure in effecting an .175

aioafieo application of the brakes with the equipment changed over orconditioned for either freight or express train operation to insure thedevelopment of a predetermined but light brake cylinder pressure upon alight reduction in brake pipe pressure being eiected through the mediumof the usual brake valve device, not shown. With the equipment changedover or conditioned for passenger train operation, the quick servicelimiting Valve device, although it will operate in the same manner aswhen the equipment is conditioned for either freight or express trainoperation, will not, as will hereinafter appear, limit the quick serviceiiow of fluid from the brake pipe, but will act to retard the rate ofreduction in brake pipe pressure. This valve device may comprise aflexible diaphragm |59 which is subject on one side to the action of aspring |66 contained in a chamber |6| constantly open, through a passage|62 to the atmosphere. At the other side of the diaphragm there is achamber |63 which is connected to the passage 92. The chamber |63 isnormally open through a passage |64 to a valve chamber |65 containing alimiting valve |66 which is adapted to be seated to close communicationbetween the chambers |63 and |65, said Valve being subject to the actionof a spring |61, which, acting through the medium of a plunger |68,tends to urge the valve toward its seat. Leading from the seat for theslide valve |63 of the control valve mechanism 5 is a quick servicepassage |69 which is connected past a check Valve |10 to the chamber|65, which check valve is adapted to prevent back flow of fluid from thechamber |65, said spring |61 acting through the medium of a plunger |1|to urge the check valve toward its seat. With the brakes released thepassage |69 is lapped by the slide valve |63 as shown in Fig. 2.

The equipment further comp-rises a quick action vent valve device |12which is associated with the emergency valve device and is mounted inthe casing thereof. This device |12 may comprise a quick action piston|13, at one side of which is a piston chamber |14 to which fluid underpressure is adapted to be supplied by way of a passage |15 when anemergency application of the brakes is initiated. At the other side ofthe piston there is a chamber i16 which is open to the atmospherethrough an opening |11 and a passage |18 in the casing. The piston |13is operatively connected by a stem |19 to the brake pipe vent valve |80contained in a chamber |8| to which the brake pipe is connected throughbrake pipe passage 46. The valve |80 is normally maintained seated on aseat rib |62 by the action of a spring |83 contained in the valvechamber |8l, and interposed between said valve and a spring seat |84carried by the casing, thus the valve closes communication through avent passage |85 leading from the valve chamber |8| to the atmosphericpassage |18. The piston |13 is provided with the usual small vent port|86 for controlling the rate of flow of fluid from the quick actionchamber to the atmosphere upon the initiation of an emergency`application of the brakes.

Control of the change-011er valve mechanism In the present embodiment ofthe invention, the operation of the change-over Valve mechanism tocondition the equipment for either passenger, express or freight trainservice depends upon the pressure of fluid carried in the signal pipe 2,and due to this the signal pipe pressure will be different for eachclass of train service, for instance, in passenger train service it willbe at the usual pressure ci about forty-five pounds, in express trainserviceV it will be higher' than forty-five pounds, say for instanceninety pounds, and in freight train service will be atmosphericpressure.

Operation of the change-over control value denice to condition thechange-over 'value device for passenger train operation When a carequipped with a iiuid pressure brake equipment embodying. the inventionis used in a passenger train, fluid under pressure supplied to thesignal pipe 2 in the usual manner hows through pipe and passage 52 tothe control chamber 5| of the change-over valve mechanism and ows fromthe passage 52 of the control chamber 55 at one side of the eXiblediaphragm 50 by way of branch passage 54, a cavity |81 in the controlslide valve 59 and passage 56. Fluid under pressure in chamber 55 actsto load the diaphragm 50 and thereby the combined spring seat and stopmember 62 against movement in a direction toward the left hand, movementin the opposite direction beingprevented by the engagement of the collar63 of the member with an annular stop lug |88 which may be integral withthe bushing 64.

When the pressure of fluid in diaphragm chamber 5| has 'been increasedto around ten pounds, diaphragm 49 is caused to flex inwardly, i. e., inthe direction toward the left hand, thereby shifting the stem 59 andassociated control slide valve and spring seat 61 in the same direction,such movement being yieldably opposed by the spring 16 which acts on theleft hand end of the stem through the medium of the spring seat. Themovement of the diaphragm, stem, slide valve and spring seat continuesuntil the spring seat is engaged by the stop 66 when the spring 68,acting through the medium of the members 62 and 66, brings the springseat, stem, slide valve 60 and diaphragm 49 to a stop in the positionsin which they are shown in Fig. 2.

It will here be understood that when the spring seat 61 and consequentlythe stem 59 and slidek valve 60 are stopped as just described, theseparts will be maintained in this position, by action of the springs 69and 16 against the movement of iiuid at the normal signal pipe pressureof fortyve pounds in diaphragm chamber 5| and acting on the flexiblediaphragm 49.

Initial charging of the equipment with the change-over control valvemechanism in position to condition the equipment for passenger trainservice With the change-over control valve mechanism positioned as justdescribed and the triple and emergency Valve devices in their normalrelease positions as shown in Fig. 2, fluid under pressure supplied tothe brake. pipe in the usual manner flows therefrom through pipe andpassage 46 and passage 41 to both the triple valve piston chamber E6 andemergency piston chamber 32.

Assuming the change-over valve device to be in position to condition theequipment for passenger train service as shown in Fig. 2 of thedrawings, fluid under pressure which is being supplied to the equalizingpiston chamber i6 flows from said chamber to a passage |89 past a springweighted check valve |96 to achamber |9| and from thence flows through apassage |92, a cavity |93 in the change-over slide valve 16 and passageand pipe 23 to the auxiliary reservoir 1. From the passage 23 fluidunder pressure flows through passage 22 to the triple valve slide valvechamber 2| and from thence flows through a port |94 in the triple valvemain slide valve I9, a passage |95 and a choked port |96 in thechange-over slide valve 16 to the change-over slide valve chamber 11,and from thence flows through passage 18 and passage and pipe 19 to theemergency reservoir 8.

Fluid under pressure flows from the slide valve chamber 11 throughpassage 89 to a cavity 248 in the change-over control slide valve 69 andfrom thence flows through passage 84 to the piston chamber 83 of thechange-over valve device. Fluid under pressiu'e also flows from thecavity 248 through passage 99 to the chamber 88 which is located at theright hand side of the flexible diaphragm l81 of the brake cylinderbuild-up control valve device, fluid under pressure in the chamber 88acting on the diaphragm 81 to maintain the valve 36 seated on the seatrib 99. Fluid under pressure in the piston chamber 83 acts on the piston14 of the change-over valve device to maintain the said device in itsconditioning position.

Fluid Linder pressure also flows past the triple valve piston by way ofthe feed groove |91 to the triple valve slide valve chamber 2l andconsequently to the auxiliary reservoir and emergency reservoir. Thepassage 23 has interposed therein a choke |98 and, at a pointintermediate this choke and the passage 22 leading to the triple valveslide valve chamber 2|, is a choked passage |99 through which fluidunder pressure flows from the passage |89 to the passage 23 andconsequently to the auxiliary reservoir and emergency reservoir. It willhere be noted that the flow of uid to the. auxiliary reservoir will beat afairly rapid rate as controlled by the feed groove |91, choke |98,and a choked passage |99.

Fluid under pressure iiows from the auxiliary reservoir passage 23through passage |95 to the slide valve chamber |94 of the control valvedevice and from thence flows to the piston chamber |070 of said deviceby Way of a passage 290, a cavity 29| in the slide valve I I` of thepilot valve device, and a passage 292.

Fluid under pressure being supplied to the emergency piston chamber 32flows through a choked passage 293 and passage 33 to the emergency valvechamber 32 and to the quick action chamber 39.

With the several parts of the equipment in their normal release positionas shown in Fig. 2, the piston chamber 9i of the relay valve device 9 isconnected to the atmosphere by way of passage 99, pipe 95, passage 94,choke |49, passage |49, chamber |45 of the inshot valve device |39,passage |44, chamber |34, choke |35, passage |29, passage |28, passage|23, a cavity 294 in the slide valve |93 of the control valve device anda passage 205. The volume reservoir 9 is connected to atmosphere by wayof pipe and passage |41 and passage |46, the latter passage leading tothe atmosphere as just described. The take-up cylinder device Il isconnected to the atmosphere by way of pipe and passage I I3, a branchpassage 206, a cavity 201 in the slide valve |93 of the control valvedevice, a passage 298, a port 299 in the triple valve main slide valveI9, a cavity 2 I 9 in the auxiliary slide valve 2|), a port 2II in themain slide valve, a restricted passage 2I2, a cavity 2I3 in thechange-over slide valve 16 and a passage 2-I4.

Fluid under pressure flows from the brake pipe to the supply reservoir||l` by way of a pipe 249, relay valve device 6 and a pipe 240.

Service application of the brakes with the equipment conditioned forpassenger train operation When it is desired to effect a serviceapplication of the brakes, a gradual reduction in brake pipe pressure iseffected through the medium of the engineers brake valve device, notshown, which reduction causes a corresponding reduction to be effectedin the pressure of fluid in both4 the triple valve piston chamber I9 andthe emergency piston chamber 32. The reduction in the pressure of fluidin the triple valve piston chamber will be at a faster rate than fluidunder pressure can ow back thereto from the triple valve slide valvechamber 2| by way of the choked passage I99 and feed groove |91, so thatthe pressure of fluid in said slide valve chamber causes the triplevalve piston |1to move outwardly in a direction toward the left hand,said piston,

through the medium of theA piston stem I8, shifting the auxiliary slidevalve 29 relative to the main slide valve |9.

As the auxiliary slide valve is thus being shifted, it laps the port |94in the main slide valve, thus closing the communication between thevalve chamber 2| and the emergency reservoir 3 and also laps the releaseport 299 in the main slide valve at substantially the same time as theport |94 is lapped. The tripple valve piston I1 closes communicationfrom both the feed groove |91 and passage |89 to the piston chamber IS,so as to prevent back-flow of fluid under pressure from the auxiliaryreservoir and valve chamber 2| to the piston chamber I9. After the :feedgroove |91 and passage |89 are thus closed, the continued movement ofthe piston causes the rear end of the auxiliary slide valve 2D touncover a service port 2|5 inthe main slide valve I9, following which,the plunger 29, mounted in the rear end of the piston stem |8 engagesthe rear surface 25 of the main slide valve. The further outwardmovement of the auxiliary slide valve by the piston and relative to themain slide valve is now resisted by the spring 3| acting through thepiston stem. Now, when a predetermined light reduction in brake pipepressure has been effected, say for instance about one pound, a sufcientfluid pressure differential is created on the piston I1, that the pistonwill be caused to move outwardly, overcoming the resistance offered bythe spring 3| and thereby shift the auxiliary slide valve to initialquick service position. The piston I1 is very sensitive to pressurediierentials and, therefore, quickly responds to a light butpredetermined brake pipe reduction to move the auxiliary slide valverelative to the main slide valve to lap the ports |94 and 209 and toclose the feed groove |91 and passage |39, and to then move theauxiliary slide valve to quick service position.

In the initial quick service position of the auxiliary slide valve 29, acavity 2 I6 in said valve connects spaced quick service ports 2 I1 and2|8 in the main slide valve. At the seat of the main slide valve, theport 2| 1 is connected to a passage 2|9 leading tothe triple valvepiston chamber I6, and the port 2| 8 is connected to a passage 220leading to the seat for the slide valve |93 of the brake cylindercontrol valve mechanism 5. The several parts of the brake cylindercontrol valve mechanism will be in their normal release position asshown in Fig. 2-and a cavity 22| in the slide valve |03 thereof connectsthe passage 220 to a 'passage 222 leading to a quick service reservoir223 of small volume, which reservoir is constantly connected to theatmosphere by way of a restricted passage 224. With the ports 2I`| and2|8 and passages 220 and 222 thus connected, .fluid under pressure ispermitted to flow from the brake pipe to the quick service reservoir 223at a Y fairly fast rate as governed by the iiow area of the restriction225 interposed in the passage 2 I9, and from said reservoir is permittedto flow to the atmosphere at a slower rate by way of the passage 224,the rate of flow of uid from the reservoir being governed by the flow ofarea of the restriction interposed in the passage 224.

It will be noted that the initial quick service flow of fluid from thebrake pipe is at a fast rate until such time as the brake pipe pressuresubstantially equalizes into the reservoir 223 and then continues at aslower rate to the atmosphere.

The initial flow ,of fluid to the reservoir produces a rapid but limitedquick service reduction in. brake pipe pressure for hastening theoperation of the triple valve device on the next car in a train. 'Ihetriple valve device on said next car then operates in a similar manner,and in this way, a quick serial response to the brake pipe reduction istransmitted fromr one car to the next throughout the length of thetrain.

After this fast but limited reduction in brake pipe pressure to thequick service reservoir, the quick service reductionis adapted tocontinue at the slower rate. This continued reduction is for' thepurpose of insuring movement of the local. triple valve parts to serviceposition.

With the auxiliary slide valve 20 in initial quick service position, acavity 226 in the valve establishes communication between two spacedfinal; quick service portsl 221 and 228 in the main slide valve, whichports are lapped at the seat of the main slide valve. When the triplevalve piston I1 and auxiliary slide valve 20 move to initial quickservice position, the shoulder 24 on the piston stem I8 engages the rearsurface 25 of the main slide valve I9, so that upon further movement ofthe piston toward service position, the main slide valve will be shiftedin the same direction to service position, in which, the piston seats onthe usual gasket which is interposed between the casing of the triplevalve device and a clamp-- ing face of the pipe bracket I3.

As the main slide valve I9 is being shifted to-v ward service position,the quick service ports 2I1 and ZIB are moved out of registration withquick service passages 225 and 220 respectively, thereby closing off anyfurther quick service flow of fluid from the brake pipe to theatmosphere by way of' the quick service reservoir 223 and passage 224.A

After the initial quick service flow of fluid from. the brake pipe hasbeen thus cut 01T, the continued movement of the main slide valve I8causes theservice port 2|5, which has been previously uncovered by theauxiliary slide valve, to be cracked open to the passage 208, so thatfluid under pres-- sure now starts to flow from the triple valve pistonchamber 2| and connected auxiliary reservoir to the take-up cylinder IIby way of port 2I5, passage 208, cavity 201 in the slide valve |03 ofthe .brake cylinder control valve mechanism 5, passage- 206 and passageand pipe I I3. Fluid under pres- .ly following this, the port 228 iscracked open to 'the passage 2|9 and to a quick service passage 229;which passage is connected to the atmosphere by way of a port 230 in theslide valve |03,

cavity 204 in said slide valve and passage 205. At the same time as thepassage 228 is cracked open to the passage 220, the portv 221 which isin communication with the port 228 by Way of cavity 226 in the auxiliaryslide valve is cracked open tov aquick servicepassage 23| which is incommunication with passage 200 by Way of a spring weighted checkl 232,check valve chamber 233, a passage 234, a choked cavity 235 in thechange-over side valve '|6 and a branch 236 of passage 208. It will herebe noted that since the quick service port 228 is in open communicationwith the passage 229, fluid under pressure is vented from the brakepipeto the atmosphere by Way of the atmospheric communication established bythe slide valve |03 of the brake cylinder control valve mechanism 5, andthat since the quick serviceport 221 is in open communication with thepassage 23| fluid under pressure is also vented from the brake pipe tothe passage ||3 and consequently to the takeup cylinder II and valvechamber I|2 of the pilot valve device.

It will here be understood that the flow of fluid from the equalizingvalve chamber 2| and connected auxiliary reservoir to the take-upcylinder I| and pilot valve chamber H2 through the cracked open serviceport will be at such a slow rate that the effect of the resultingreduction in auxiliary reservoir pressure lon the continued movement ofthe triple valve piston Il toward service position will be negligible.The reason for thus opening the service port before permitting the nalquick service flow of fluid from the brake pipe to begin is to effect areduction in auX- iliary reservoir pressure before the pressure in thetake-up cylinder and chamber I I2 is increased by the quick service flowof fluid.` In this connection it will be noted that if the iinal quickservice flow of fluid from the brake pipe were permitted to take placebefore the service port were opened and the triple valve parts should,for any reason, come to a stop before the service port is open, thequick service flow of fluid from the brake pipe would build up the iiuidpressure in the take-up cylinder and chamber I I 2, and since noreduction in auxiliary reservoir pressure could occur, fluid underpressure could not be released from said cylinder and chamber upon anincrease in brake pipe pressure. By arranging the ports in the mannerjust described, a reduction in auxiliary reservoir pressure will occurbefore the nal quick service flow of fluid from the brake piper takesplace, so that the above referred to objectionable feature is notpresent in the equipment shown.

The triple valve piston il and associated slide valves I9 and 20continue to move to the service position in which the piston seals onthe gasket interposed between the casing of the triple valve device andthe pipe bracket |3. With the main slide valve I in service position,the service port 2|5 is in full registration with the passage 208 andthe quick service ports 228 and 221 are in full registration withpassages 220 and 23| respectively.

With the main slide valve of the triple valve device in serviceposition,'fluid under pressure ows from the triple valve slide valvechamber 2| and connected auxiliary reservoir to the take-up cylinderdevice by way of the service port 2|5,

passage 208, cavity 201 in the slid-e valve |03, passage 206, andpassage and pipe H3. vFluid under pressure thus supplied to thev passage|I3 alsoV ative to the brake cylinder piston, said push rod flows to theslide valve chamber H2 of thepilot valve device.

Fluid under pressure being thus` supplied to the take-up cylinder deviceII causes the piston and stem thereof to move outwardly and actuate` thebrake rigging to take up the slack therein and to bring the usual brakeshoes, not shown, intocontact with. the car wheels. The brake rigging asit is moved by the take-up cylinder draws the push rod of the brakecylinder: I2 forwardly relbeing automatically locked, in the usualmanner, by means of the well known latch box mechanism, in its outermostposition with relation to the piston when the brake cylinder piston ismoved outwardly by fluid under pressure supplied thereto.

When the pressure of fluid inthe take-up cylinder device II has beenincreased suiciently to cause it to function in the` manner justdescribed, the pressure of uid in the slide valve chamber ||2 of thepilot valve device, acting on that portion of the rear face of thepiston |06 which is encircled by the seat rib I I5, causes the pistonand thereby the slide valve III to move outwardly against the resistanceoffered by the spring |09. The face of the piston |06 is provided withan annular seat rib, which rib, when the piston is moved to itsoutermost position, seals against a gasket clamped to the casing, so asto prevent leakage of iluid past the periphery of the piston from thevalve chamber II2 to the atmosphere. It will here be understood that thepilot valve device will remain in its normal position until the pressureof uid in chamber I I2 is increased to about thirty pounds. When thispressure is attained the piston |06 mov-es outwardly and breaks the sealbetween the gasket and seat rib, whereupon the entire area of the innerface of the piston |06 is subjected to the pressure of fluid in chamber||2, and as a result the piston will move with a snap action to itsextreme outer position.

The slide valve III of the pilot valve device, as it is being movedtoward its outer position, laps the passage IIS, thereby cutting offcommunication from the auxiliary reservoir to the valve chamber |I2, andlaps the passage 200, thereby cutting oli the communication` from thecontrol slide valve chamber |04 and connected auxiliary reservoir to thecontrol piston chamber |00. After the passages |I3 and 200 are lapped,the cavity 20| in the slide valve III, which remains in communicationwith passage 202, is brought into open communication with the passage231 which leads to the atmosphere, so that fluid under pressure is nowvented from the piston chamber to the atmosphere. Further, as theslidevalve I I I moves toward its extreme outer position, and justbefore it reaches this position, it uncovers one end of a passage 238 tothe valve chamber H2, the other end of this passage having beenpreviously connected to the triple valve slide valve chamber 2| uponmovement of the triple valve main slide valve I9 to service position, sothat fluid under pressure flows from the triple valve chamber andconnected auxiliary reservoir to the pilot slide valve chamber II2 andmaintains the pilot piston |06 and slid-e valve III in their extremeouter position.

With the piston chamberv |00 of the control valve device vented to theatmosphere as just described, uid under pressure in the control slidevalve chamber |04 causes the control piston 99 to move outwardly againstthe opposing action of the spring I 0| into sealing engagement with agasket which is clamped to the casing, the piston in its traversecarrying with it the` control: slide valve |03. 'I'he slide valve |03.asit is thus being moved, laps.r the passage 206, thuscutting offcommunication from the passage.208,A to. the 5 1 take-up cylinder deviceI I. At substantially theA same time as the passage 206 `is lapped, thecavity.. 201 connectspassage208 to passage |28, so that fluidl underpressure now ows from passage208 through. cavity 201, passagey |28,passage |29, 1Q-

choke 35, inshot valveI chamber I 34, past` the unseated inshot valve|33, passage |44, chamber |45, passage |46..and passage and pipe |41tothe volume reservoir 9. From the, passage |46 f1u1' d under pressureflows through choke |49, passage, 94, pipe 95, and passage 96 totherelay piston chamberV 91. At substantially. the same time as. thelcavity 201 in the control slide valve I03vconnects the passages 209 and|23Y together,r the cavity 204 in the valve connects thequickservice 20passages,k |69 andl 229A together. With, tl'iislatter.. communicationestablished the quick service flow of iuvid from the brake pipe by wayoi the passage 229, instead of being to the atmosphere, willv be tothebrake vcylinder by way of cavity 204, passage |69, past the check valve|10 embodied in the,V quick service limiting valve device |53, throughVvalve chamber |65-, past the unseated quickr service limiting valve |66through passage I64 diaphragm chamber |63, passage 92, a cavity 2 39 3omove inwardly from the position in which it is `Y shown in Fig, l,y andthe piston as it is thus moved, causes the usual brake cylinderexhaustvalve to clse and the brake cylinder supply valve to open. With thesupply valve open, fluid under pressure ows from the supply reservoirI0` by 40 way of a pipe 240, relay valvel deviceand a pipe 24| to thebrake cylinder I2, causing the brake cylinder to act to apply thebrakes.

Fluid under pressure flows from passage |28 through passage |21 to thediaphragm chamber 45 |22- of the valve device II1, and when the pressureoi fluid in this chamberhas been increased, by such low, toaround thirtypounds, the flexible diaphragm |I8, being subjected to this pressureVtogether with the pressure of iuidacting on the inner seated area of thevalve |23 will be caused to ex outwardly against the opposing pressureofthe spring I2I, and as a result the Valve |23 will be unseated, sothat fluid under pressure will iiow from the passage `I21 to the take-up55 cylinder device by way of passage |26 and passage and pipe II3. Thispermits the relay piston chamber and take-up cylinder pressures to buildup together. The valve |23 will now. remainlunseated until, as willhereinafter appear, the brakes are being released.

Fluid under pressure supplied to the passage 94, besides flowing to therelay piston chamber, also ows to the piston chamber |39 v0f the inshotvalve-device by way of cavity 239m the changeover slide valve 16,passage 92, cavity 22| in the control slide valve |03, a passage 242, acavity 243 in the emergency main slide valve 35, passage |42, volumereservoir |4| and passage |40. It will here be noted that since the flowof fluid..m under pressure to the chambers |39 and |45 of the'inshotvalve mechanism is from the auxiliary reservoir, the pressure of fluidin these chambersl will increase together when a service application ofthe brakes is beingeiected, so that the spring "N |38 acts through themedium of the inshot piston |36 and its stem |31 to maintain the inshotvalve |33 open, thus the inshot valve mechanism is rendered ineiectiveto vary the rate of flow of iiuid under pressure to the relay pistonchamber Sl.

When the relay piston chamber pressure has been increased to around ninepounds fluid at brake cylinder pressure in diaphragm chamber |63 of thequick service limiting valve device |58 causes the nexible diaphragm |59to flex toward the right hand against the opposing action of the spring|60, whereupon the spring itl acting through the medium of the plunger|68 causes the Valve |66 to seat and cut oi the quick service flow offluid from the brake pipe by way of the passage 229. The seating of thequick service limiting valve device |66 does not however cut off all ofthe quick service flow of iluid from the brake pipe to the relay pistonchamber but does act to restrict the rate of quick service flow asgoverned by the flow capacity of the restricted passage 235 in thechange-over slide valve 16.

vWhen the brake pipe pressure has been reduced sufficiently to producethe desired brake application the engineers brake valve device is moved,as is usual, to lap position. Now when the auxiliary reservoir pressurein the triple valve piston chamber 2| has been reduced by flow of fluidtherefrom to the relay piston chamber and volume reservoir 9 slightlybelow the reduced brake pipe pressure, the triple valve piston l1 andauxiliary slide valve 20 move relatively to the main slide valve toservice lap position in which the auxiliary slide valve will lap theservice port 2|5 and thereby cut o-iT the further flow of uid to therelay valve device and volume reservoir, and will also lap the quickservice port 227, thereby cutting oi the further quick service flow offluid from the brak-e pipe to the relay piston chamber and volumereservoir 9 by way of cavity 227 in the triple valve main slide valvei9.

Upon a service reduction in the pressure of fluid in the emergencypiston chamber 32, the emergency piston 33 and auxiliary slide valve 36are shifted outwardly, i. e., in the direction toward the right hand,relative to the main slide valve 35, by fluid in the emergency slidevalve chamber 3l. As the piston is thus shifted, it closes thecommunication between the piston chamber 32 and the passage 203connected to pass-age 38 leading to the quick action chamber 39 andslide valve chamber 3l, and at substantially the same time, theauxiliary slide valve establishes the usual atmospheric communication byway of registering ports 253 and 25| in the auxiliary and main slidevalves respectively and through which iiuid under pressure is ventedfrom the valve chamber 3l and connected quick action reservoir 39 at arate substantially equal to the service rate of reduction in thepressure of fluid in the triple valve piston chamber 32, so that theoperating pressure diierential on the emergency piston 33 issubstantially destroyed. By reason of this, unintentional furthermovement of the piston and auxiliary slide valve toward emergencyposition is prevented.

Brief summary of the quick service venting of fiuicl under pressure fromthe brake pipe in eecting a service application of the brakes It will beapparent from the foregoing descripticn, that the equipment is capableof functioning to effect a local quick service reduction in `brake Apipepressure in three stages after a reduction in brake pipe pressure hasbeen effected through the'medium of the usualy brake valve device; Thefirst stage of this local reduction is at a rapid rate tothe small quickservice reservoir 223, the amount vof reduction on the local carv beingadequate to insure the movement of the triple valve device on the Anextcar to initial quick service'position, thus insuring the promptpropagation lof quick service action throughout the train. Thesecondstagel of quick service reduc,-l tion is due vto the ventingfoffluid from the quick service reservoir 223 to the atmosphere by' way ofthe `choked passage 22,4, consequently a slow Venting of iiuid from thebrakepipe to the atmosphere takes place, lso as to reducethe'brake pipepressure suflcientlyfto insure movement Vof the limiting valve device|58 and also by way of'ay communication which is not controlled by thelimiting valve device. When the pressureoffluid g,

in the relay piston chamber and volume reservoir has been increased toaround nine pounds, the quick service limiting valve device functions toelecta reduction in the rate of now of 'fluid from the brake pipe. Thisnal reduction in brake pipe pressure begins before the triple valvepiston Il and slide valves 9 and' 20 are Ain service position andtherefore contributes to the promptmovement of the triple valve partstoY service position and continues asrlong as the triple valveslide poseof insuring the triple valve parts remaining in service position untilthe Vdesired brake cylinder pressure is obtained. "It will be understoodthat the final 'reduction is alsov for the purpose of smoothing out ordampening surges which may have been created in the lfluid underpressure in the brake-pipe and yis at a slow rate so as not to createother detrimental vsurges in the brake pipe fluid.

Release of `the brakes after a. service application with the equipmentconditioned for passenger train operation To efect a release of thebrakes after a service application, iiuid Vunder-pressure is suppliedtothe brake pipe l and flows therefrom to the `triple valve pistonchamber I6 and emergency vpiston chamber 32 in the same manner as hashereinbefore been described in connection kwith y,

the initial charging ofthe equipment.

To initiate the release of the brakes, it is customary to rst move thebrake valve to release position, in which nuid under pressure -issupplied directly from the main reservoir, not shown, to

the brake pipe, and then, after a predetermined interval of time haselapsed,'to move the brake valve to running position, in which fluid atfeed vvalve pressure is supplied to the brake pipe.

The initial supply of fluid at high pressure to the brake piperapidly'increasesthe brake lpipe f i pressure, the high head of pressureat the front end of the train being. adapted to cause a rapid flow offluid und'er'pressure'vtoward the reary of the train, so as toaccelerate the release of the 40 valves are inservice position and isfor the pur;-

'ilo

brakes and the recharging korfthebrake equipment on the cars at the rearend of the train.

The rapid increase in the brake pipe pressure creates a pressuredifferential on the triple valve piston I1 which causes the piston andthereby the slide valves I9 and 20 to promptly move to their normalrelease position in which they are shown in Fig. 2. With the piston I1in this position the feed groove |91 and feed passage |39 are open, so

that fluid under pressure is permitted to flow at a restricted rate fromthe piston chamber I6 through both the feed groove |91 and feed passage|89 to the triple valve slide valve chamber 2| and auxiliary reservoir1.

, Further, with the triple valve' parts in release position, fluid underpressure is supplied at a restricted rate from the fully chargedemergency reservoir lto the triple valve slide valve chamber 2| andauxiliary reservoir 1 by way of pipe and passage 19, passage 18,change-over slide valve chamber 11, restricted port |96 in thechange-over slide valve 16, passage |95 and port |94 in the triple valvemainslide valve I9. Due to the restricting of the ow of fluid from thebrake pipe to the triple valve slide valve chamber and auxiliaryreservoir and the flow of fluid thereto from the fully charged emergencyreservoir, the amount of fluid `takenfrom the brake pipe will not begreat, so that more fluid will flow toward the rear of `the train, thushastening the recharge of the brake pipe on carsat the rear end of thetrain.

The restricted port |99 in` the change-over slide valve 19 limits therate at which fluid flows fromthe emergency reservoir to such an extentthat after the brake valve is moved from release position to-runningposition, and the brake pipe pressure on the cars drops to cr below thatsupplied by the feed Valve device at the locomotive, the pressure ofiiuid in the triple valve slide valve chamber will be less than thebrakepipe pressurein piston chamber 21. By reason of this, unintentionalmovement of the equalizing valve parts-from a release position to quickservice or service position in releasing the brakes is prevented.

With the triple valve slide valves in release position, uid underpressure is vented from the relay piston chamber 9,1 to the atmosphereby way of passage 96, pipe 95, passage 94, choke |49, passage |46,chamber |45 of the inshot valve device |30, passage |44, past the openinshot valve |33, valve chamber |34, choke |35, passages Ii and |28,cavity 201 in the control slide valve |03, passage 293, cavity 209 inthe triple valve main slide valve I9, cavity 2|0 in the triple valveauxiliary slide valve 20, port 2| 9 in the main slide valve I9, passagel2|2, cavity 2|3 in the change-over slide valve 16 and passage 2I4.

i Since the volume reservoir 9 is in open communication with the passage|46 by way of pipe and passage I 41, fluid under pressure is vented fromsaid reservoir through the communication just traced, which leads fromthe passage |46 to the atmosphere.

At the same time as iiuidunder pressure is being vented from the relaypiston chamber 91 and volume reservoir 9, fluid under pressure isvented'from the take-up cylinder device I| by way of pipe and passageII3, passage |26, past the unseated valve |23, passage |21 and thecommunication, just traced, which leads from the passage |28 to theatmosphere. Now when the 'pressure of the take-up cylinder device |I andrelay piston chamber has been reduced, by the venting of uid therefrom,as just described, to

around thirty pounds, the valve I 23 will be moved into seatingengagement with the seat rib |24 by the action of the spring |2| andwill thereby cut off the flow of fluid from the takeup cylinder deviceby way of passage |21 and communications therefrom to the atmosphere.

With the triple valve main slide valve I9 in release position, thepassage 238 is in registration with the port 299 in the slide valve, sothat fluid under pressure is vented from the valve chamber II2 of thepilot valve device with the iiuid uri-der pressure being vented from therelay piston chamber 91. Now when the pressure of iluid in the relaypiston chamber 91 and consequently in the slide valve chamber II2 of thepilot valve device has been reduced to a low degree, say, for instance,to about ve pounds, the spring I 09 acts to cause the piston of thepilot valve device to move inwardly to its innermost position in whichthe gasket |I4 seats upon the annular seat rib II5.' The piston actingthrough the medium of the stem IIO shifts the slide valve i II to itsinner position in which, the cavity Elli in the valve establishescommunication from the passage 290 to the passage 202, so that fluidunder pressure is supplied from the control slide valve chamber |94` tothe control piston chamber |09. The pressures of fluid acting on theopposite sides of the control piston 99 will equalize quickly, so thatthe spring IOI acts tion, fluid under pressure being vented from therelay valve piston chamber 91 and volume reservoir by way of passage|28, flows through cavity 204 in thel sli-de valve and passage 205 tothe atmosphere.

Further, with the slide valve |03 in this position, the cavity 201therein establishes communication from the passage 206, leading from thetake-up cylinder device II, to the passage 208, so that fluid underpressure is vented from the take-up cylinder device by way of port 209in the triple valve main slide valve I9, cavity 2I0 in the auxiliaryslide valve 20, port 2|I in the main slide valve, restricted passage2I2, cavity 2|3 in the change-over slide valve 16 and passage 2M.

It will here be noted that when the slide valve III of the pilot valvedevice moves to its inner or release position the passage |I3 leadingfrom the take-up cylinder device II is connected to the slide valvechamber |I2, so that fluid under pressure from the take-up cylinderdevice equalizes into said chamber, but the equalized pressure acting onthe inner seated area of the real` face of the piston is insufficient tocause the piston to move outwardly against the opposing pressure of thesprings |99, so that the piston and slide valve will remain in theirinner position. Since the passage IIS is connected to the atmosphere thechamber 91 will be vented with the take-up cylinder device.

With the control slide valve |03 in its inner or release position, fluidunder pressure is vented from the piston chamber |39 of the inshot valvedevice by way of passage I 40, volume chamber |4I, passage |42, cavity243 in the emergency main slide valve, passage 242, a laterallyextending cavity 246 in the control slide valve |03, a passage 241, port209 in the triple valve main slide valve and the atmosphericcommunication from said port 209.

'passages 220 and 222.

It will be understood that by delaying the lrelease operation ofthetake-up cylinder device until after the brake cylinder pressure has beenreduced to a low degree and then reducing the brake cylinder pressure ata rate faster than that of the reduction in the take-up cylinderpressure, the automatic unlatching operation of the latch box mechanism,carried by the brake cylinder, will be insured before such vmechanism issubjected to the releasing action; of the take-up cylinder device, thuseliminating the possibility of damage to the latch mechanism by thetakeup cylinder device.

The increase in brake pipe pressure to effect the release of the brakescauses. the emergency piston 33 and thereby the auxiliary slide valve 36to move to their normal release position in which they are shown in Fig.2 of the.k drawings.

Graduated release of the brakes with the equipment conditioned forpassenger train operation,

In passenger train operations it is very desirable to reduce thev brakecylinder pressure in steps or increments, in other Words to graduatethe'release of the brakes.

Assuming the several parts of the equipment to be in service position,as vhereinbefore described, and it is desired to graduate the release ofthe brakes, the brake valve is first moved to release position toquickly increase the brake pipe pressure sufliciently to cause the partsof the equipment to move to release position, andzis then moved to lapposition, in which the flow of fluid from the main reservoir toY the'brake pipe is closed olf. p

With the several parts of the equalizingY valve device in releaseposition, fluid under pressure is vented from the volume reservoir 9vand relay piston chamber 91 in the same manner as hasl already beendescribed in connection With the full or complete release of thebrakes.; This causes the relay valve device E to operate to initiate areduction in brake cylinder pressure. With the brake valve in lapposition, it is obvious that there Will be no further increase in brakepipe pressure and as a result of this ,the pressure of uid in the triplevalve slide valve chamber 2| Will be increased by the flow of fluid fromthe fully charged emergency reservoir. When the pressure in valvechamber 2| slightly exceeds the brake pipe pressure in the triple valvepiston chamber l5, fluid under pressure in said chamber 2| causes thepiston and thereby the auxiliary slide valve 20 to moveoutwardlyrelative to the main slide Valve. The piston and slide valvemove but a very short distance when the slide valve laps the port |94 inthe main slide valve and thereby closes oif the oW of iiuid to the valvechamber 2|, and since,with the port |94 closed, no further increase inthe pressure of fluid in the valve chamber Will ,be` effected,

the; triplevalve piston and auxiliary slide valve will either come toazstop or-have a tendency to do` so.

- Infpracticeit has been found that when the brake valve is movedfromrelease position to lap position in graduating the release of thebrakes, the vreduction in brake pipe pressure on the head cars ofthetrain caused bythe ilow of fluid from said lcars toward the rearV of thetrain is such as to permit thepressure of fluid in the triple valveslide valvev chamber to vunintentionally move the triple valve pistonand auxiliary slide valve to initial quick service position, the fluidpressureydifferential created on said piston being sufcientto overcomethe resistance offered by the spring 3| and plunger 29. It will be notedthat When-the auxiliary valve assumes this position,`r the controlslide" valve |03 is' in its uppery most or application position inWhichthe initial quick service communication from the triple valvedevice toithe quick service chamber 223 and the atmosphere is cut` olfso that no quick service flow of fluid from the brake pipe is permitted.If this quick `service communication Werefpermitted to remain openingraduating the release of the brakes quick service action would bepropagated throughout the' length. of the train and as a result Wouldcause an application of the brakes to be effected when the release ofthe brakes is intended. With the quick service communication `cut offAby the control slide valve the possibility of this undesirable actionis eliminated.

At substantially the same time as the port |94 is lapped, the auxiliaryslide valve also laps the port 209 in the main'slide valve I9 and thuscloses 'off the exhaust flow of fluidfrom the'voltune reservoir 9 andrelay piston chamber 91. NOW when the brake cylinder pressurer has beenreduced slightly below the reduced relay piston chamber pressure, therelay valve device 6 is caused to operate to close the brake cylinderexhaust communication to the atmosphere. Since, With the brake cylinder`exhaust communication closed, no further reduction in brakev cylinderpressure occurs, the several movable parts of the relay vvalve devicecome to a stop.

When it is desired to make another step of reduction in brake cylinder.pressure, the brake valve may be moved from lap to running position andWhen the `desired reduction in brake cylinderpressure is attained, thebrake valve is returned to lap position. The increase in4 brake pipepressure effected upon movement of the brake valve to'running positioncauses thetriple valve piston and thereby the auxiliary slide valve 29to be. shifted toV release position, in which the ports |94 and 209 areagain opened to the triple valve chamber 2| and the passage 2| l,respectively, the opening of the port |94vpermitting the flow of iiuidfrom the emergency reser- Voir toV the valve chambers andthe opening ofthe port 209 permitting fluid under pressure to iioW from the volumereservoir 9 and relay piston chamber 91 to the atmosphere, the resultingreduction in the relay piston chamber causing the ,relay valve device tooperatetd effect the corresponding reduction in brake cylinder pressure.With the brake' valve inl lap position the triple valve piston andauxiliaryr slide valve Will again move to close off the floWrof fluidfrom the volume reservoir and relay piston chamber, so that the relayvalve device will vbecaused to operate to close off the flow of liuidfrom the brake cylinder to the atmosphere. y v

It will be understood 'that by means ofthe brake valve, the triple valvedevice and relay valve device may be caused to operate to reduce thebrake cylinder pressure in as many successive steps as desired, untilsuch` time as the emergency reservoir pressureiequalizes into the auX-iliary reservoir. After such equalization any further increase in brakepipe pressure moves the triple valve piston and auxiliary slide valve torelease position, Where they remain until the brakes are completelyreleased.

Conditioning the change-oper 'valve device ,for

express and freight train operations and operation of the equipment inexpress and freight train operations The operation of the change-overcontrol valve device and change-over valve device to condition the brakeequipment for express and freight train operations is substantially thesame as that of the corresponding devices described in theaforementioned pending application of Clyde C. Farmer and Ellis E.Hewitt, Serial No. 94,372.

It Will here be understood that the slide valve i5 of the change-overvalve device Will be caused to move to the position in which it is shownin Fig. 3 for either express or freight train operations and that thecontrol valve device therefore assumes different positions as shown inFigs. 3 and 4. In Fig. 3 the control valve device is shown in positionto cause the control valve device to move to express train position andin Fig. 4 is shown in position to cause the control valve device to moveto freight train position.

The slide valve 16 in its change-over position for express or freighttrain operations laps the passage 236 so that When thel triple valvedevice moves to its final quick service position there Will be noquickfservice flow,v of uid from the brake pipe to the take-up cylinder.There will however be a quick service flow of iiuid from the brake pipefirst to the atmosphere by Way of the restricted passage 229, cavity 230in the control slide valve |93, cavity 204 in the slide valve andpassage 205 until such time as the control slide valve is caused to moveto its outermost position in which the cavity .204 is out ofcommunication with the atmospheric' passage 205 and connects the quickservice passages 229 and |69 together. With the passages 229 and |69thus connected together fluid under pressure is vented from the brakepipe to the volume reservoir 9 and relay piston chamber 9'! until suchtimeas the pressure of iiuid in said reservoir and chamber has beenincreased to around nine pounds When the quick servicelimiting valvedevice |58 operates to close off the further quick service flow of fluidfrom the brake pipe.

From this it Will be seen that the quick service flow of uid from thebrake .pipe to the -atmosphere begins as soon as the quick service port228 in the triple valve main slide valve is opened tothe quick serviceypassage 229 and continues until the atmospheric passage 205 is lappedby the control slide valve |93. At substantially the same time as thepassage is lapped the cavity Re@ in the control slide valve connects thequick service passages 229 and |69 together so that the quick serviceflow of fluid is to the brake cylinder, such flow continuing until cutoff by the quick service limiting valve device |58 When the brakecylinder pressure has been increased to around nine pounds.

Other operations ofthe brake equipment Will be substantially the same asthat of the equipment covered in ythe Farmer and Hewitt application,Serial No. 94,372 and since these operations have been described indetail in said applicationit' is deemed unnecessary to describe them inthe present application.

Having now described our invention, What We claim as new and desire tosecure by Letters Patent, is:

1. In a uid pressure brake, in combination, a brake pipe, a brakecontrolling valve device operative upon a reduction in brake pipepressure iirst to a quick service position to effect a local reductionin brake pipe pressure and then to an application position to effect anapplication Vof the brakes and operative upon a subsequent increase inbrake pipe pressure in steps or increments to graduate the release ofthe brakes, means operative for rendering the brake controlling valvedevice ineifective to effect a reduction in brake pipe pressure when, ingraduating the release of the brakes, the brake controlling valve deviceassumes said quick service position, and valve means operative uponmovement of the brake-controlling valve device from said quick serviceposition to application position for effecting the operation of saidmeans.

2. In a iluid pressure brake, in combination, a brake pipe, a brakecontrolling valve device operative upon a reduction in brake pipepressure rst to aquick service position to effect a local reduction inbrake pipe pressure and then to an application position to effect anapplication of the brakes and operative upon a subsequent increase inbrake pipe pressure in steps or increments to graduate the release ofthe brakes, means responsive to variations in fluid pressures forrendering the device ineffective to effect a reduction in brake pipe4pressure when, in graduating the release of the brakes, the deviceassumes said quick service position, and means responsive to fluid underpressure supplied thereto by the brake controlling valve device when thedevice is in application position for effecting the operation of saidmeans.

3. In a fluid pressure brake, in combination, a brake pipe, a brakecontrolling valve device operative upon a reduction in brake pipepressure first to a'quick service position to establish a communicationthrough which fluid under pressure is adapted to be Vented from thebrake pipe and then to an application position to effect an applicationof the brakes and operative upon a subsequent increase in brake pipepressure in steps or .increments to graduatethe release of the brakes,uid pressure responsive means operative for closing said communicationfor rendering the brake controlling valve device ineffective to ventfluid under pressure from the brake pipe when, in graduating the releaseof the brakes, the brake controlling valve device assumes itscommunication establishing position, and valve means operative uponmovement of the brake controlling valve device to said applicationposition for effecting the operation of said fluid pressure responsivemeans.

4. In a fluid pressure brake, in combination, a brake pipe, a brakecontrolling valve device operative upon a reduction in brake pipepressure to first establish a quick service communication through whichuid under pressure is locally Vented from the brake pipe and to thenestablish a communication through which fluid under pressure is suppliedto effect an application of the brakes, and operative upon a subsequentincrease in brake pipe pressure in steps or increments alternately torelease 'and release lap 'position to graduate the release of thebrakes, means subject to opposing uid pressures and responsive to one ofsaid fluid pressures for closing said communication to thereby renderthe device ineffective to effect a reduction in brake pipe pressure,Whenin graduating the release of the brakes, the device moves beyondsaid release lap position and assumes said quick service position, andmeans responsive to fluid under pressure supplied thereto by said brakecontrolling valve device when'the device is in application position foreffecting the operation of said means.

5. In a uid pressure brake, in combination, a brake pipe, a brakecontrolling valve device operative upon a reduction in brake pipepressure to first eect a' local quick service reduction in brake pipepressure and to then effect an application of the brakes and operativeupon a subsequent increase in brake pipe pressure in steps or incrementsto effect a graduated release of the brakes, a valve normallyestablishing communication through Which the quick service reduction inbrake pipe pressure is effected, means subject to opposing fluidpressures and responsive to a reduction in one of the pressures forclosing said communication to thereby render the device ineffective toeffect a reduction in brake pipe pressure when, in graduating therelease of the brakes the device assumes quick service venting position,and means responsive to the pressure of fluid supplied thereto by thebrake controlling valve device When the device is in applicationposition for eiecting'the opera tion of said means.

6. In a fluid pressure brake, in combination, a brake pipe, a brakecontrolling valve device operative upon a reduction in brake pipepressure first to a quick service position to effect a local reductionin brake pipe pressure and then to an application position to effect afurther local reduction in brake pipe pressure and to effect anapplication of the brakes and operative upon a subsequent increase inbrake pipe. pressure in steps or increments to graduate the release ofthe brakes, means operative for rendering said device ineffective toeffect a reduction in brake pipe pressure When in graduating the releaseof the brakes the brake controlling valve device assumes said quickservice position, and valve means upon movement of the brake controllingvalve device to application position for effecting the operation of saidvalve means.

'7. In a fluid pressure brake, in combination, a brake pipe, valve meansoperative upon a reduction in brake pipe pressure for first establishinga quick service communicatian through which fluid under pressure isvented from the brake pipe and for then closing said quick servicecommunication and establishing a communication through which fluid underpressure is supplied to effect an application of the brakes andoperative upon a subsequent increase in brake pipe pressure foreffecting a release of the brakes, means subject to opposing pressuresand operative upon a reduction of one of said pressures for preventingthe flow of fluid through said quick service communication when ineffecting the release of the brakes said valve means assumes its brakepipe venting position, and a valve device controlled by said valve meansfor effecting the operation of said means.

8. In a fluid pressure brake, in combination, a bra-ke pipe, valve meansoperative upon a reduction in brake pipe pressure for rst establishing avquick service communication through Which uid'under pressure is ventedvfrom. the brake pipe and for then `closing said quick servicecommunication and establishing a'communication through which fluid underpressure is supplied to effect an application of the brakes andoperative upon a subsequent increase in brake pipe pressure foreffecting a release 'of the brakes, means operable to prevent the quickservice flow of 'fiuid from the brake-pipe through said quick servicecommunication when in releasing the brakes said valve means assumes itsbrake 'pipe venting position, and a valve device operative by fluidunder pressure supplied by said valve means when the valve means is inbrake application position for effecting the operation of said means.

9. In a fluid pressure brake, in combination, a brake pipe, valve meansoperative upon aV reduction in brakepipe pressure for first establishinga quick service communication through which fluid under pressure isvented from the ibrake pipe and for then closing said communication andestablishing a `communication through which fluid under pressure is:supplied to effect Yan `application of the brakes and operative upon asubsequent increase in brake "pipe pressure foi-Veffecting a release ofthe brakes, means operative to a position to close said quick servicecommunication to thereby prevent the quick service 110W of uid from thebrake pipe When-in releasing the brakes said valve means assumes brakepipe venting position, and a valve'device operative by fiuid underpressure supplied by said valve means in effecting an application of thebrakes for effecting the. operation of said means. i

10. In a fluid pressure brake, in combination, a brake pipe, valve meansoperative upon areduction in brake pipe pressure forflrst establishing aquick service communication through which `iiuid under pressure 'isAvented from the brake pipe, for then closing said Acommunication andfor establishing a lcommunication through which fluid under pressure issupplied to effect an application of the brakes and operative upon asubsequent increase in brake pipe pressure for effecting a release ofthe brakes, a control valve device operative for also closing saidcommunication to prevent the venting of fluid from the brake pipe intheevent of the movement of said a quick service communication throughwhich fluid under pressure is vented from the brake pipe, for thenclosing said communication and forl establishing a communication throughwhich fluid under pressure is supplied to effect anapplication of thebrakes and operative upon a subsequent increase in brake pipe pressurefor effecting a release of the brakes, means subject to opposing fluidpressures and operative upon a reduction in one of said pressures foralso closing said communication to prevent the venting of fiuid from thebrake pipe in the event of the movement of said valve means to brakepipe venting position in effecting the releaseof the brakes,

said means being operative upon substantially the complete release ofthe brakes to its communication open position, and a valve deviceoperative upon a predetermined increase in the pressure of fluidsupplied by said valve means in effecting an application of the brakesfor reducing said pressure to effect the operation of said means.

12. In a fluid pressure brake, in combination, a brake pipe, valve meansoperated upon a reduction in brake pipe pressure to rst vent fluid underpressure from the brake pipe to then cut ofl'` the venting of fluid fromthe brake pipe and then supply fluid under pressure to effect anapplication of the brakes, a valve normally establishing communicationthrough which fluid under pressure vented from the brake pipe is adaptedto flow and operative to close said communication, and means responsiveto the pressure of fluid supplied by said valvemeans in effecting anapplication of the brakes to effect a reduction in iiuid pressure tocause said fluid pressure responsive means to operate to actuate saidvalve to close said communication.

13. In a fluid pressure brake, in combination, a brake pipe, a quickservice reservoir, valve means operated upon a reduction in brake pipepressure for first venting fluid under pressure from said brake pipe tosaid reservoir to` effect a local reduction in brake pipe pressure andfor then cutting off the venting of uid from the brake pipe and forsupplying fluid under pressure to eect an application of the brakes, andmeans normally establishing communication through which iluid underpressure vented from the brake pipe by said valve means flows to saidreservoir and a movable abutment subject to opposing fluid pressures andoperative upon the venting of fluid from one side thereof to actuatesaid means and a valve device operative by fluid under pressure suppliedby said valve means, in effecting an application of the brakes, to ventfluid under pressure from said side of said abutment.

14. In a fluid pressure brake, in combination, a brake pipe, a quickservice reservoir, valve means operated upon a reduction in brake pipepressure for first venting fluid under pressure from said brake pipe tosaid reservoir to effect a local reduction in brake pipe pressure andfor then cutting ofi the venting of fluid from the brake pipe andsupplying uid under pressure to effect an application of the brakes, andfluid pressure responsive means interposed between said valve means andreservoir normally establishing communication through which fluid underpressure vented from the brake pipe by said valve means flows to saidreservoir and operative upon a reduction in fluid pressure actingthereon to close said communication, and means responsive to thepressure of fluid supplied by said valve means in effecting anapplication of the brakes for reducing the pressure of fluid acting Vonsaid means. i

15. In a fluid pressure brake, in combination, a brake pipe, a quickservice reservoir, valve means operated upon a reduction in brake pipepressure for rst venting fluid under pressure from said brake pipe tosaid reservoir to effect a local reduction in brake pipe pressure andfor then cutting offthe venting of fluid from the brake pipe andsupplying fluid under rpressure to eiTect an application of the brakes,and means interposed between said valve means and reservoir normallyestablishing communication through which fluid under pressure ventedfrom the brake pipe by said valve means flows to said reservoir, meanssubject to opposing iluid pressures and operative upon a reduction inone of said pressures to close said communication said means beingadapted to maintain said communication closed during the release of thebrakes, and means operative by fluid under pressure supplied by saidvalve means in effecting an application of the brakes for effecting theoperation of said means.

16. In a fluid pressure brake, in combination, a brake pipe, a take-upcylinder device, a passage through which fluid under pressure is adaptedto be supplied to effect an application of the brakes, a brakecontrolling valve device operative upon a reduction in brake pipepressure to vent fluid under pressure from the brake pipe and to supplyfluid under pressure to said take-up cylinder device, and valve meansnormally estab'- lishing communication through which fluid underpressure vented from the brake pipe flows and another communicationthrough which fluid supplied by the brake controlling valve device flowsto the take-up cylinder device and operative upon an increase in take-upcylinder pressure to close both of said communications and to establishanother communication through which iluid under pressure supplied bysaid brake controlling Valve device flows to said passage and also tothe take-up cylinder device, the communication through which fluid underpressure is vented i' from the brake pipe being closed to preventundesired venting of fluid from the brake pipe in the event of movementof the brake controlling valve device to its brake pipe venting positionin releasing the brakes.

17. In a fluid pressure brake, in combination, a brake pipe, a take-upcylinder device, a passage through which fluid under pressure is adaptedto be supplied to effect an application of the brakes, a brakecontrolling valve device operative upon a reduction in brake pipepressure to vent iluid under pressure from the brake pipe and to supplyfluid under pressure to said take-up cylinder device, and valve meansnormally establishing communication through Which fluid under pressurevented from the brake pipe flows and another communication through whichfluid supplied by the brake controlling valve device flows to thetake-up cylinder device and operative upon an increase in take-upcylinder pressure to close both of said communications and to establishanother communication through which fluid under pressure supplied bysaid brake controlling valve device flows tosaid passage and also to thetake-up cylinder device, the communication through Which fluid underpressure is vented from the brake pipe being closed to prevent undesiredventing of fluid from the brake pipe in the event of movement of thebrake controlling valve device to its brake pipe venting position inreleasing the brakes, said brake controlling valve device beingoperative upon increasing the brake pipe pressure in steps or incrementsto graduate they release of the brakes and said valve means beingmaintained in its communication closing position to prevent fluid underpressure from being vented from the brake pipe when in graduating therelease of the brakes the brake controlling valve device moves to itsbrake pipe venting position.

18. In a fluid pressure brake, in combination, a brake pipe, a take-upcylinder device, a passage through which fluid under pressure is adaptedto be supplied to effect an application of the brakes, a brakecontrolling valve device operative to brake application position tosupply iluid under pressure 75 to the take-up cylinder device and at thesame time to vent fluid under pressure from the brake pipe, and valvemeans normally establishing communication through which fluid underpressure supplied by the brake controlling valve device flows to thetake-up cylinder device and another communication through which uidvented from the brake pipe ilows to the atmosphere and operative upon anincrease in take-up cylinder pressure for cutting 01T the ow of fluid tothe takeup cylinder and the iioW of uid vented from the brake pipe tothe atmosphere and for then establishing communication through whichfluid supplied by the brake controlling valve device flows to saidpassage for establishing another communication through which fluidvented from the brake pipe flows to said passage.

19. In a fluid pressure brake, in combination, a brake pipe, a take-upcylinder device, a passage through which iluid under pressure is adaptedto be supplied to eiect an application of the brakes, a brakecontrolling valve device operative to brake application position tosupply fluid under pressure to the take-up cylinder device and at thesame time to vent iiuid under pressure from the brake pipe, valve meansnormally establishing communication through which fluid under pressuresupplied by the brake controlling valve device iiows to the take-upcylinder device and another communication through Which fluid ventedfrom the brake pipe iiovvs to the atmosphere and operative upon anincrease in take-up cylinder pressure for cutting oi the oW of iluid tothe take-up cylinder and the flow of fluid vented from the brake pipe tothe atmosphere and for then establishing communication through whichfluid supplied by the brake controlling valve device liovvs to saidpassage for establishing another communication through which fluidvented from the brake pipe ovvs to said passage, and means operativeupon the attainment of a predetermined pressure in said passage forcutting off the flow of uid from the brake pipe to the passage.

20. In a fluid pressure brake, in combination, a brake pipe, a take-upcylinder device, a passage through which fluid under pressure is adaptedto be supplied to effect an application of the brakes, a brakecontrolling valve device operative to brake application position tosupply fluid under pressure to the take-up cylinder device and at thesame time to vent fluid under pressure from the brake pipe, valve meansnormally establishing communication through which uid under pressuresupplied by the brake controlling valve fluid supplied by the brakecontrolling valve dei vice iioWs to said passage for establishinganother communication through which fluid vented from the brake pipeflows to said passage, and valve means responsive to fluid underpressure in said passage forv limiting the amount of uid vented from thebrake pipe to the passage.

21. In a fluid pressure brake, in combination, a brake pipe, a brakecontrolling valve device operative upon a reduction in brake pipepressure to first vent fluid under pressure from the brake pipe, to thenterminate such venting, and to then supply fluid under pressure toeffect an application of the brakes and to vent uid under pressure fromthe brake pipe, valve means normally establishing communication throughwhich fluid first vented from the brake pipe flows anda communicationthrough Which uid being finally vented from the brake pipe initiallyovvs to the atmosphere, said valve means being operative to close bothof said communications and to establish another communication throughwhich thev final venting of fluid from the brake pipe is continued,means operative by fluid under pressure supplied by the brakecontrolling valve device for eifecting the operation of said valvemeans, and valve means operative by fluid under pressure supplied by thebrake controlling valve device for limiting the flow of uid from thebrake pipe by Way of the last mentioned communication, said brakecontrolling valve device being responsive to steps or increments ofincrease in brake pipe pressure for 4graduating the release of thebrakes, and said valve means being adapted to remain in the position towhich it has been operated during the graduated release of the braketopreventr the venting of fluid from the brake pipe when in releasingthe brakes the brake controlling valve device moves to its firstmentioned venting position.

ELLERY R. FITCH. GLENN T. MCCLURE.

of the above numbered patent requiring correction as follows: Page l5,sec- Wrh.. #han CERTIFICATE CE CORRECTION; 1 I Patent No; 2,1o6,h8oJanuary 25, 1958u ELLEEY E. EITCE, ET AI.

It is hereby Certifiedthat error appears in the printed specification 1ond Column, line lO, Claim 8, for the word"operable read operative; pagel lh., first column, line 19, claim l2, before "and" insert fluidpressure responsive means operative upon a reduction in fluid pressurefor effecting the operation of said valve; and that the said LettersPatent should be read with these Corrections therein that the same mayconform to thev record of the oase in the Patent Office. I

Signed and sealed this 15th day of March, A., D. 1958.

Henry Van Arsdale, (Seal) y Acting Commissioner of Patentso Y

